I have never heard audible voices
By that, I assume you mean except by using your physical ears. Someone hearing audible voices and who thinks they could be coming through his physical ears is confused. It's not an ideal situation.
[Rather the communications arise in my mind as ideas which I know are not my ideas.]
Where are we told to expect any such "communication"?
Paul gives a warning about ideas that pop up. Do we ask where they come from?
2 Corinthians 10:3 For though we walk in the flesh, we do not war after the flesh:
4 (For the weapons of our warfare are not carnal, but mighty through God to the pulling down of strong holds; )
5 Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ;
We are also warned about how the Devil tries to deceive people. Every bad thought that pops up in our minds are not our own. Rejecting such thoughts as undesirable and embracing good thoughts instead is a way of not giving way to the Dark Side.
James 4:7 Submit yourselves therefore to God. Resist the devil, and he will flee from you.
It's true. The man tempted to commit adultery could go kiss his wife when he thinks bad thoughts about other women. Do something good instead when you have a bad thought. The temptations of the Devil can be used to remind us to do good; and do that enough, you may find the Devil fleeing, giving up. Now you may not know if the bad thought was yours or the Devil's -- but it doesn't matter too much. Either way, you will find such bad thoughts tend to go away if you bring every thought into captivity to the obedience of Christ.
How do you know they are not"your ideas"?
My own ideas are the result of two things: First, I am observing things in reality and thinking about them as a result. If someone knocks at my door, I will think, "I hear someone knocking." My thought is related to something happening around me. Second, nothing may be happening around me, but I'm contemplating things. There is a mental process going on that I can observe. If I want to multiply 26 times 3 in my mind, my thoughts may go like this, "20 times 3 is 60, and 6 times 3 is 18, and 60 plus 18 is 78, so the answer is 78."
Ideas that come from outside myself are not like either of those two. They appear suddenly without my needing to "think about" things. I can give you an example. When I was reading Revelation, an angel would sometimes tell me to stop and look something up. Now the angel could have told me what he wanted me to know; but he didn't do it that way. He'd tell me to look it up. The most fascinating example of that involved the words "Amen," "faithful" and "true." When I looked the words up in Hebrew, I found out they were all spelled with the same three consonants A-M-N. Of course, that wasn't true in Greek or English. I found other places where that kind of thing happened when the angel told me to look things up.
When a prophet says something like, "The Word of God came" he means God sent him an idea, an idea so complete, it could contain pictures and sounds.
We also read how Jesus could read minds. He never got confused about whose thoughts belonged to who. Every person is unique; and every thought that comes from that person has something like an identification mark or stamp on it.
[Sometimes they may contan "words" in English, other times no -- other times it's the idea and I would need to supply words myself to try to tell others.]
If you are supplying the words, can it be said to be a revelation from God?
If I showed you a picture and asked you what it was, you'd supply your own words to the best of your ability. Some visions are like that too. The prophet is shown something; and if his mind is working right, he will supply the right words. Think about Jeremiah.
Jer 1:11 Moreover the word of the LORD came unto me, saying, Jeremiah, what seest thou? And I said, I see a rod of an almond tree.
12 Then said the LORD unto me, Thou hast well seen: for I will hasten my word to perform it.
Does that make sense? In English, not too much. It starts to make more sense if you look at the Hebrew. "Almond tree" is "shaqed" and "hasten" is "shaqad." (Vowels don't matter that much in written Hebrew.)
[For example, in a vision, I may see things without words being used.]
This differs from a normal daydream in what way?
My daydreams are not very vivid; and I'm aware that I'm creating the objects in my own imagination. A vision is different since it's much more vivid and I'm not involved in thinking things up, I'm observing things. I may be thinking, but it's as an observer. I know it's not my mind making things happen.
[Almost everyone has the ability to receive ideas like that, but few don't when awake.]
Are you thinking of any place in the bible that teaches this?
Yes, certainly. When Israel came out of Egypt, all were given the chance to hear the Voice of God. They did not want to hear it. Indeed they heard it as a threatening loud trumpet sound and perceived very little of the intelligence in it. They could understand the Decalogue, the Ten Sayings which are often called the Ten Commandments. The rest they could not understand since their hearts were hard and they refused to soften them. They wanted Moses to act as intercessor for them. They wanted Moses to talk with God and then tell them about it. So they got the Written Word -- the Torah -- after rejecting the Living Word.
David in his day urged people to be willing to hear the Voice of God for themselves.
Psalm 95:6 O come, let us worship and bow down: let us kneel before the Lord our maker.
7 For he is our God; and we are the people of his pasture, and the sheep of his hand. To day if ye will hear his voice,
8 Harden not your heart, as in the provocation, and as in the day of temptation in the wilderness:
9 When your fathers tempted me, proved me, and saw my work.
10 Forty years long was I grieved with this generation, and said, It is a people that do err in their heart, and they have not known my ways:
11 Unto whom I sware in my wrath that they should not enter into my rest.
The Gospel is preached from Heaven too.
Revelation 14:6 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people,
Everyone in Paul's day had received the Gospel, one way or another. Everyone.
Colossians 1:23 If ye continue in the faith grounded and settled, and be not moved away from the hope of the gospel, which ye have heard, and which was preached to every creature which is under heaven; whereof I Paul am made a minister;
It was preached then to every living creature; and it continues to be preached from Heaven to everyone.
More later since this post is probably already too long.
